Beer Alchemy: Adding Raspberry Puree to the "Fermentables" list

I'm about to add some Vintner's Harvest Red Raspberry Puree to my wheat beer's secondary. I want to calculate the gravity and the ABV using Beer Alchemy, but I don't know how. I tried adding a new fermentable in BA, but couldn't find the info it needed.
Any ideas?

I'm about to do the same thing to a split batch of saison.

It says on the can that it ranges from 1.040-1.055 IIRC.

My recipe is 11 gallons, and I'm adding the Rasberries to only one carbouy. So in a few months I can tell you how much gravity the one 49 oz. can added to my saison compared to the saison without it...

If anyone has a more theoritical way of calculating this or personal experience, I'd be interested in hearing it.